HTTP 500 SERVER While Building website

I am building a website for my lab, and we build it based on a server provided by our campus.

I am editing the website through the Elementor page. When I save the website, I always get a SERVER 500 ERROR. The error happened when I try to save a text edit.

When I try to access the admin website(https://tsbresearch.web.illinois.edu/wp/wp-admin/update-core.php), I always get the issue of a white page and I cannot touch anything after that. It says, there has been a critical issue with your website. Please check your email.

Could you help me to figure out what is wrong here? This issue is very critical and we cannot make any progress on our website.

Thank you so much?for your help!

The page I need help with: [log in to see the link]